This invention relates to a computer system equipped with a storage system, and more particularly, to a technique for monitoring a storage capacity.
Storage systems provide logical volumes (LUs) to application servers by statically allocating storage areas of physical disks. However, the LUs have the below-mentioned problems.
That is, for instance, there is a problem in that storage capacities of physical disks which are allocated to application servers become larger than storage capacities which are actually used for the application servers (namely, over provisioning). This is because storage capacities which are used for application programs operating on the application servers cannot be correctly grasped. There is another problem in that operational costs required to change the capacities of the LUs are high.
As a technique for solving those problems, thin provisioning is known. Storage systems provide volumes (thin provisioning volumes) realized by the thin provisioning to the application programs operating on the application servers.
Thus, the storage systems can provide the thin provisioning volumes which are recognized as volumes having larger storage capacities than the storage capacities of physical disks which are actually allocated. Upon reception of write requests from the application programs operating on the application servers to the thin provisioning volume, the storage systems dynamically allocate an unused storage area of a storage pool to the thin provisioning volume which are requested by the above-mentioned write requests.
On the other hand, JP 2004-110321 A discloses a data management system for managing used storage capacities of storage systems for each project in an business-to-business collaboration application.